The present invention relates to the field of motor vehicles and, more particularly, to a device for automatically controlling a tail light on a motor vehicle so as to avoid motor vehicle accidents.
A device or system for automatically switching on the hazard lights of a motor vehicle is known from the above-referenced patent application Ser. No. 07/083,042. This device switches on a warning tail light of the motor vehicle (e.g., the hazard lights) upon sensing substantially the same conditions as would lead the vehicle operator to manually switch on the hazard lights; in particular:
(1) when the motor vehicle speed (instantaneous or average speed) falls below a prescribed threshold speed for a prescribed period of time;
(2) when the instantaneous motor vehicle speed falls below the time average vehicle speed by a prescribed amount for a prescribed period of time;
(3) when the closure speed between the motor vehicle and another motor vehicle, either in front or in the rear, exceeds a prescribed value;
(4) when the distance between the motor vehicle and another motor vehicle, either in front or in the rear, falls below a prescribed value;
(5) when one road wheel of the motor vehicle does not rotate at substantially the same speed as another road wheel or other road wheels of the vehicle (thus indicating wheel spinning, skidding or brake lock); and/or
(6) when the motor vehicle is mechanically disabled for any reason (e.g., is out of fuel or has a flat tire).
This device normally will simply switch on the conventional flashing hazard lights of the motor vehicle in response to one or more of the above conditions. However, it is important that the device does not switch on the hazard lights in situations where they are not needed, since frequent, unnecessary flashing of hazard lights would cause confusion to other motor vehicle operators. For example, it is clearly not necessary (and, indeed it is undesirable) to flash hazard lights in the stop-and-go city traffic environment.
It is therefore an objective to provide a device or system for automatically controlling the hazard lights of a motor vehicle which avoids and eliminates the problem that the hazard lights may be unnecessarily or undesirably switched on.